この
「この」 means “this” and directly points to 「このシャツ」, the shirt being shown or discussed. A customer can use it when identifying a nearby item.
シャツ
「シャツ」 means “shirt” in 「このシャツ」 and 「シャツが未使用」. It can follow a demonstrative such as 「この」 to identify a particular shirt.
を
In 「このシャツを買いました」, 「を」 marks the shirt as the thing that was bought. The reusable pattern 「名詞を動詞」 marks what an action is done to.
買いました
「買いました」 means “bought” in 「このシャツを買いました」. It is the polite past form related to 「買う」; use 「〜を買いました」 to say that you bought something.
サイズ
「サイズ」 means “size”; in 「サイズが合いません」, it refers to the size that does not fit. It also appears before another noun in 「もっと大きいサイズ」 and 「大きいサイズ」.
が
In 「サイズが合いません」, 「が」 marks the size being described. In 「シャツが未使用なら」, it marks the shirt whose condition is relevant; the pattern 「Xが…」 presents X as the thing being described.
合いません
「合いません」 means “does not fit” in 「サイズが合いません」. It is the polite negative form related to 「合う」; use 「サイズが合いません」 when clothing is not a suitable fit.
レシート
「レシート」 means “receipt” in 「レシートとタグ」. In a shop, it can be mentioned when asking whether the proof of purchase is still available.
と
In 「レシートとタグ」, 「と」 joins the receipt and the tag as two items. The reusable pattern 「AとB」 means “A and B.”
タグ
「タグ」 means “tag” in 「レシートとタグ」. In this shop conversation, it refers to the tag that the customer has kept with the receipt.
は
In 「レシートとタグはまだありますか」, 「は」 sets the receipt and tag as the topic of the question. The pattern 「Xはありますか」 asks whether X is present or available.
まだ
「まだ」 means “still” in 「まだありますか」 and asks whether the receipt and tag remain available. It is useful when checking whether something expected to remain is still there.
あります
「あります」 means that the receipt and tag are present or being kept in 「レシートとタグはまだありますか」. It is the polite form related to 「ある」; 「〜はありますか」 asks whether an item is available or present.
か
In 「ありますか」, 「か」 marks the sentence as a question. In 「返品か交換」, it connects two alternatives and means “or.”
どちら
「どちら」 refers to either member of two items; with 「も」 in 「どちらも」, it means “both,” referring here to the receipt and tag. Use 「どちら」 when identifying or choosing between two options.
も
In 「どちらも袋に入れてあります」, 「も」 gives 「どちら」 the meaning “both of the two.” The expression 「どちらも」 is useful when saying that both items meet the same condition.
袋
「袋」 means “bag” in 「袋に入れてあります」. The phrase identifies the bag as the place where both items have been put and kept.
に
In 「袋に入れてあります」, 「に」 marks the bag as the place into which the items were put. A reusable pattern is 「場所・容器に入れる」 for putting something into a place or container.
入れて
In 「袋に入れてあります」, 「入れて」 contributes the action of putting both items into the bag; with 「あります」, the phrase says they have been put there and remain there. It is the て-form related to 「入れる」, and 「〜に入れてあります」 describes something intentionally kept in a place.
それ
In 「それなら」, 「それ」 refers to the information just given, namely that both the receipt and tag are in the bag. Together, 「それなら」 means “in that case.”
なら
In 「それなら」, 「なら」 makes the previous situation the basis for the next statement: “if so” or “in that case.” The reusable pattern 「Xなら、…」 responds based on a stated condition or premise.
返品
「返品」 means “return” in 「返品か交換」. In a shop conversation, it refers to giving the purchased item back rather than exchanging it.
交換
「交換」 means “exchange” in 「交換のお手伝い」 and 「交換したいです」. In this dialogue, it means changing the shirt for a larger size; 「交換のお手伝い」 is a useful phrase for help with an exchange.
の
In 「交換のお手伝い」, 「の」 links 「交換」 with 「お手伝い」, giving the meaning “assistance with an exchange.” The pattern 「AのB」 links B to A in this kind of noun phrase.
お手伝い
「お手伝い」 means “assistance” or “help” in 「交換のお手伝いができます」. The phrase 「お手伝いができます」 can be used to offer help with a customer’s request.
できます
In 「お手伝いができます」, 「できます」 means “can help,” while in 「試着できますか」 it means “can try on.” It is the polite form related to 「できる」 and is used to describe an action or service as possible.
もっと
「もっと」 means “more” in 「もっと大きいサイズ」 and increases the degree of 「大きい」. Use it before a describing word when asking for or referring to a greater degree.
大きい
「大きい」 means “large” or “big”; in 「もっと大きいサイズ」, it describes a size larger than the current one. It directly comes before the noun 「サイズ」.
したい
In 「交換したいです」, 「したい」 expresses the speaker’s wish to exchange the shirt. The reusable polite pattern 「〜したいです」 says that someone wants to do an action.
です
In 「交換したいです」, 「です」 politely closes the statement that the speaker wants to exchange the shirt. The pattern 「〜たいです」 is used to express a polite desire.
未使用
「未使用」 means “unused” in 「シャツが未使用なら」. Here it describes the condition required for the exchange, and it is combined with 「なら」 to mean “if the shirt is unused.”
できる
In 「交換できると思います」, 「できる」 means that an exchange is possible or can be carried out. It is the plain form related to polite 「できます」; use 「〜できる」 to say that an action is possible.
思います
In 「交換できると思います」, 「思います」 means “I think” and presents the possibility as the staff member’s judgment rather than an absolute promise. It is the polite form related to 「思う」; 「〜と思います」 is a common way to state an opinion.
どこ
「どこ」 means “where” in 「どこで試着できますか」. The pattern 「どこで + action」 asks where an action can take place.
で
In 「どこで試着できますか」, 「で」 marks the place where the action of trying on occurs. A reusable pattern is 「場所で + action」 for an action performed at a location.
試着
In 「試着できますか」, 「試着」 means “trying on clothing.” Together with 「できますか」, it asks whether the speaker can try the larger size on; this is a useful shop phrase when asking to try on clothes.
試着室
「試着室」 means “fitting room” in 「試着室はあのディスプレイの後ろです」. The pattern 「試着室は〜です」 can be used to tell someone where the fitting room is.
あの
「あの」 means “that” in 「あのディスプレイ」 and points to a specific display visible to the speakers. It comes directly before the noun it identifies.
ディスプレイ
「ディスプレイ」 means “display” in 「あのディスプレイの後ろ」. Here it identifies the shop display used as a reference point for the fitting room’s location.
後ろ
「後ろ」 means “behind” or “the back” in 「ディスプレイの後ろ」. The pattern 「Aの後ろ」 describes something located behind A.